The invention relates to an amylaceous composition for mixtures based on synthetic or natural binders or bonding agents employed in the manufacture of certain textile or paratextile products, particularly of the composite textile or fabric type.
The mixtures concerned are generally denoted in the art and hereafter by the term "compound". Furthermore, the synthetic or natural binders, which represent the essential constituent and, in certain cases, the only constituent of the compounds, are denoted by the term "latex"; they are in the form of aqueous dispersions of synthetic polymers or of natural rubber.
The said mixtures based on synthetic or natural binders also called compounds, find numerous applications in processes known in themselves of manufacturing textile and paratextile products, particularly of the composite textile or fabric type; certain steps of the said processes constitute bonding operations, particularly at the moment of assembling the constituent parts of the textile composites, such as carpets, tufted carpets or needleloom carpets, and others of the type comprising a foam "backing" or again of textile which constitute a secondary laminating, the assembly being generally denoted by the term "double backing" when the "backing" is of textile material.
The viscosity of the compounds must be such that they penetrate just sufficiently into the textile material to give the desired adherence between the constituents parts of the product.
Besides the one or more synthetic polymers and/or natural rubber, the compounds comprise generally fillers, particularly inorganic fillers, conferring on the finished textile products, flame-proofing properties, rigidity, color and the like. They may also contain, among other things, one or several of the following constituents:
anti-oxidants PA1 anti-foaming products PA1 plasticizers PA1 thickeners PA1 vulcanizing agents PA1 emulsifiers PA1 dispersing agents.
To be competitive, the textile products thus manufactured with the use of compounds based on synthetic or natural bonding agents or latex, must respond particularly to criteria of solidity which, for example in the case of carpets of the "double backing" type, are manifested by a sufficient resistance to the separation of the constituent parts of the carpet.
It has already been proposed, with the object of improving thereof the properties of viscosity and/or the cohesive power, to introduce into the composition of the above-said compounds, various thickening agents of which certain are amylaceous products, constituted by:
either pregelatinised starches,
or gelatinised starch pastes,
or starches in granular form, insoluble in cold water, possibly modified previously by chemical means, and possibly employed in the presence of certain chemical agents, which can lower the gelatinisation temperature thereof.
In this connection, it is possible to mention the French Pat. No. 2,332,130.
None of the solutions thus proposed has led to results satisfactory in all respects.
Thus the use of pregelatinised starches or starch pastes, leads to the obtaining of bonding compositions having excessive viscosities, incompatible with the operating conditions on a machine.
The use of granular starches can result, for its part, in precipitation problems, in particular in the field of full immersion needleloom carpets.
On the other hand, the instantaneous adherence power is non-existant, and the cohesive power on emerging from drying, may be judged insufficient.